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101.
CASE DESCRIPTION: A 4-month-old American Paint filly was evaluated because of sudden onset of ataxia that progressed to recumbency. Five additional horses from the same and neighboring premises developed signs of poor performance, generalized weakness, ataxia, and recumbency; 2 of those horses were also evaluated. A new batch of a commercial feed supplement had been introduced to the horses' diet on each farm within the preceding 3 days. CLINICAL FINDINGS: Other than recumbency, findings of physical and neurologic examinations of the foal were unremarkable. The other 2 horses had generalized weakness and mild ataxia, and 1 horse also had persistent tachycardia. The foal had mild leukocytosis with neutrophilia, hyperglycemia, and mildly high serum creatine kinase activity. Results of cervical radiography, CSF analysis, and assessments of heavy metals and selenium concentrations in blood and vitamin E concentration in serum were within reference limits. Feed analysis revealed high concentrations of the ionophore antimicrobial salinomycin. TREATMENT AND OUTCOME: The 5 affected horses survived, but the foal was euthanized. At necropsy, a major histopathologic finding was severe vacuolation within neurons of the dorsal root ganglia, which was compatible with ionophore toxicosis. The surviving horses developed muscle atrophy, persistent weakness, and ataxia. CLINICAL RELEVANCE: In horses, ionophore toxicosis should be considered as a differential diagnosis for acute weakness, ataxia, recumbency, or sudden death. Furthermore, ionophore toxicosis should be considered as a cause of poor performance, weakness, muscle wasting, and cardiac arrhythmias in horses. Surviving horses may have impaired athletic performance.  相似文献   
102.
This study determined in vitro anthelmintic efficacy of three plant species: Trema orientalis, Urtica dioica and Zanthozylum capense on nematode larvae of small ruminants. Dried leaf samples (40 g) were extracted in 70% ethanol, in portions of 10 g and concentrated to 100 ml. Half and one quarter of the original crude extract were both made to 100 ml. Rectal faecal material from 10 Merino sheep and 25 Nguni goats was pooled within species and thoroughly hand-mixed. Dung samples, each of 5 g were cultured for 12 days at 27 °C. On day 13, 4 plates were watered and 4 others treated with ethanol to correct for solvent effect on mortality. The design was 2 (animal species)?×?3 (plant species)?×?3 (extract concentrations). In each of three runs, three plates were treated with each crude extract in three incremental concentrations. Surviving L3 larvae were isolated, counted and mortalities became indices of anthelmintic efficacy. Data from nematode larval mortality were analysed to determine the effect of animal species, plant species, concentration and their interactions. Efficacy was affected by concentration (P?=?0.0001), animal species (P?=?0.0046), plant species (P?=?0.0572), the interactions of animal species and concentration (P?=?0.0010), plant species and concentration (P?=?0.0123) and concentration × animal × plant species (P?=?0.0435).  相似文献   
103.
The Salmonella sp. genus is identified in several species, and the zoonosis it causes is one of the most important types worldwide. The specifics of salmonellosis vary according to the function of the serovar involved, the species affected, age and predisposing factors. However, few cases of equine salmonellosis have been reported. This study presents ten confirmed salmonellosis cases in equines in southern Brazil. Six were adult animals with stress factors preceding the disease, while four were foals, three of which presented with hyperacute manifestations. The main clinical signs were diarrhea, anorexia, and hyperthermia. Lesions varied in distribution and severity, although fibrinonecrotic or necrohemorrhagic enteritis was observed in all animals, mainly in the large intestine (large colon and cecum—8/10) and small intestine (3/10). Substantial liquid content, mainly hemorrhagic, was observed in all animals. The most characteristic microscopic lesion was mucosa necrosis, which is often accompanied by fibrin deposition, followed by necrosis of follicular centers and vascular changes. Bacterial isolation revealed seven isolates. Five were serotyped, and the serovars Typhimurium and Anatum were associated with two cases each, while Muenster was associated with a case whose lesion pattern varied. Immunohistochemical staining was positive in all cases. All diagnoses were based on the clinical history, macroscopic and histological lesions, and the bacterial isolation and/or immunostaining associated with histological lesions.  相似文献   
104.
Dromedary camels complaining from conception failure or abortion were investigated and their herders interviewed in Al Ahsa province, Kingdom of Saudi Arabia (KSA) during 2013 and 2015. The most important reproductive disorder according to the responders is uterine infection (60.2%) followed by obesity (22.3%) then physiological conditions (hormonal disturbances; 7.8%), adhesions (3.9%) and repeat breeders (2.9%). Of the camel herders, 78.6% reported previous occurrence of abortion in their herds and 46% reported abortion cases in the last season (2015/2016), while 21.4% reported no history of abortion. Most of the responders (97.1%) do not call a veterinarian for cases of abortion in their herds and 53.4% do not discard aborted materials. The majority of the herders (76.7%) deny that handling aborted materials or touching vaginal fluids can result in human infection, or replied they do not know. Uterine swab samples were collected and tested by PCR for seven potential pathogens and sera tested for antibodies against bovine viral diarrhea virus (BVDV) and Brucella. Five pathogens were identified in infected uterine samples, namely Coxiella burnetii (36%), Campylobacter spp. (27%), Brucella spp. (17%), Salmonella spp. (13%), and Chlamydia spp. (7%). Sero-prevalence of Brucella and BVDV was 8.2 and 29.1% in overall sera, respectively, and varies with regard to the region. The findings of the present study demonstrate that reproductive disorders dominated by uterine infections and abortions are widespread in dromedary camels in KSA.  相似文献   
105.
A nitrogen (N) balance digestion trial was conducted to determine the protein requirement of collared peccaries (Pecari tajacu). In a 4 × 4 Latin square design, four captive adult male peccaries were fed four isoenergy diets containing four different levels of N (11.7, 16.3, 22.8, and 26.7 g N/kg of dry matter—DM). After 15 days of adaptation, a total collection of feces and urine was carried out for five consecutive days. Regression analyses between N intake and N in feces and urine allowed to calculate the metabolic fecal nitrogen (MFN = 2.3 g N/kg of dry matter intake—DMI) and daily endogenous urinary N (EUN = 185 mg N/kg0.75). Likewise, by regression analyses between consumption of nitrogen and the nitrogen balance (NB = N ingested ? N excreted, mg N/kg0.75), a daily requirement of 514 mg N/kg0.75 was calculated. Therefore, if food intake is unrestricted, collared peccaries require a minimum in their diet of about 5.4% crude protein on DM basis. These values are almost as low as those found for browsing and frugivorous wild ruminants, which reinforce the proposition that peccaries’ digestive physiology is nearer to that of domestic and wild ruminants than domestic pigs. This relatively low protein requirement of collared peccary and its great ability to digest protein reveal the relevance of the forestomach for the species on nitrogen/protein metabolism and allow the use of diets with lower crude protein levels than the commercial ones used for the domestic pig, which reduces feed costs.  相似文献   
106.
Brucellosis is a zoonotic disease worldwide distributed and having the economic as well as public health importance. The prevalence of brucellosis among sheep flock having history of abortions was studied. A total of 229 samples comprising of 157 blood and 72 clinical samples (vaginal swabs) were collected from 157 animals. Clinical samples were processed for the isolation of Brucella melitensis. Serum samples (n = 157) were tested by Rose Bengal plate test (RBPT) and i-ELISA. A total of 68 (43.31%) and 104 (66.24%) samples were positive by RBPT and ELISA, respectively. Brucella isolates (n = 2) were recovered from clinical samples. Both isolates demonstrated amplification for bcsp 31 and IS711 genes. On AMOS PCR, both the isolates amplified at 731 bp, i.e., belongs to B. melitensis species. The incidence of B. melitensis in a migratory flock warns the thorough testing and culling of Brucella-infected sheep from the flock on a continuous basis; otherwise, such incidence will be routine and poor farmers will be at a loss.  相似文献   
107.
Alternative poultry production with special reference to free range broilers has increased significantly since the nineties in many regions of the world. Numerous factors influence the productive performance of this type of broilers: genotype (namely the use of naked neck animals), feeding and access to an outdoor area. The aim of this paper is to study the influence of each of these factors on the productive performance of free range broilers under commercial rearing conditions. A total of 3200, day old chicks of both sexes from naked neck and normally feathered genotypes were used in this trial. After a joint initiation phase, animals were divided into four different treatments with the combination of two concentrates (high vs low energy content) and management (access to outside park or not). Experiment lasted a total of 12 weeks. Live weight date was recorded weekly and a samples of animals from the trial were sacrificed at the age of 8, 10 and 12 weeks, when carcass characteristics were determined. Besides sex, the only factor that seems to affect growth characteristics was genotype as naked neck animals had poorer growth rates than normally feathered. No effect was detected on carcass yields and percentages of carcass components for any of the variables. From the data presented in this trial the practises associated with free range production are of relative inconsequence to the technical animal production parameters and can only be justified by a pressing need to differentiate these products from standard poultry products in what concerns both welfare issues and meat characteristics. The results also indicate that genetic material from alternative poultry production in Europe can be a useful option in poultry production development projects in the tropics.  相似文献   
108.
In recent years host antimicrobial peptides and proteins have been recognised as key mediators of the innate immune response in many vertebrate species, providing the first line of defense against potential pathogens. In chickens a number of cationic antimicrobial peptides have been recently identified. However, although these peptides have been studied extensively in the avian gastrointestinal tract, little is known about their function in the chicken reproductive organs and embryos. Chicken Liver Expressed Antimicrobial Peptide-2 (cLEAP-2) has been previously reported to function in protecting birds against microbial attack. The aim of this study was to investigate the expression of cLEAP-2 gene in the chicken reproductive organs, as well as in chicken embryos during embryonic development, and to determine whether cLEAP-2 expression in the chicken reproductive organs was constitutive or induced as a response to Salmonella enteritidis infection. RNA was extracted from ovary, oviduct, testis and epididymis of sexually mature healthy and Salmonella infected birds, as well as from chicken embryos until day ten of embryonic development. Expression analysis data revealed that cLEAP-2 was expressed in the chicken ovary, testis and epididymis as well as in embryos during early embryonic development. Quantitative real-time PCR analysis revealed that cLEAP-2 expression was constitutive in the chicken epididymis, but was significantly up regulated in the chicken gonads, following Salmonella infection. In addition, expression of cLEAP-2 during chicken embryogenesis appeared to be developmentally regulated. These data provide evidence to suggest a key role of cLEAP-2 in the protection of the chicken reproductive organs and the developing embryos from Salmonella colonization.  相似文献   
109.
This project was conducted to investigate the comparative efficiency of competitive ELISA (cELISA), standard Agar Gel Immunodiffusion Test (AGID) and Precipitinogen Inhibition Test (PIT) for the diagnosis of Peste des Petits Ruminants (PPR) in Pakistan. To deal with this, serum samples from 198 sheep and 82 goats were collected from three different government livestock farms and all the samples were run simultaneously with the three serological tests. The samples found positive for PPR antibodies through cELISA, AGID and PIT were 96 (34.2%), 60 (21.4%) and 72 (25.7%), respectively. Kappa statistics were applied to evaluate the concordance between the laboratory-based test (cELISA) and field-based tests (AGID and PIT). Kappa statistics scores for cELISA versus AGID and PIT were 0.6343 (95% Confidence Interval CI 0.5231–0.7456) and 0.7134 (95% Confidence Interval CI 0.5987–0.8281), respectively, which indicate a “substantial” agreement between cELISA and AGID and “significant” agreement between cELISA and PIT. AGID and PIT revealed relative diagnostic sensitivities with cELISA of 59.3% and 69.7% and relative diagnostic specificities of 98.3% and 97.2%, respectively. The data suggested that for mass screening and control of PPR, these serological tests proved practical in the absence of cELISA since they have high relative diagnostic specificities and a satisfactory relative diagnostic sensitivities.  相似文献   
110.
Verticillium dahliae, a soilborne plant pathogen, causes wilt disease in many important crops. We reported previously that the mating type gene MAT1-2-1 is spread to isolates of this asexual fungus. However, we did not determine whether V. dahliae is homothallic or heterothallic because the opposite mating type gene, MAT1-1-1, had not been identified. In the present study, we identified the MAT1-1-1 gene from an isolate lacking MAT1-2-1 and the mating type idiomorphs of V. dahliae. Each isolate we tested contained either the MAT1-1 or MAT1-2 idiomorph, indicating that the asexual fungus V. dahliae is potentially heterothallic.  相似文献   
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